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61.
Frederic Vandeperre Ruth M. Higgins Julio Sánchez‐Meca Francesc Maynou Raquel Goñi Pablo Martín‐Sosa Angel Pérez‐Ruzafa Pedro Afonso Iacopo Bertocci Romain Crec’hriou Giovanni D’Anna Mark Dimech Carmelo Dorta Oscar Esparza Jesús M. Falcón Aitor Forcada Ivan Guala Laurence Le Direach Concepción Marcos Celia Ojeda‐Martínez Carlo Pipitone Patrick J. Schembri Vanessa Stelzenmüller Ben Stobart Ricardo S. Santos 《Fish and Fisheries》2011,12(4):412-426
Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta‐analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no‐take area. CPUE of both target species and the marketable catch increased gradually by 2–4% per year over a long time period (at least 30 years). The influence of the size of the no‐take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no‐take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no‐take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs. 相似文献
62.
Depletion study and estimation of withdrawal periods for florfenicol and florfenicol amine in pacu (Piaractus mesopotamicus)
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Tamires Valim Marques Jonas Augusto Rizzato Paschoal Rafael Simões Coelho Barone José Eurico Possebon Cyrino Susanne Rath 《Aquaculture Research》2018,49(1):111-119
The intensive production of farmed fish is at a global all‐time high, and the control of bacteria proliferation in fish farms requires the frequent use of antimicrobials. This practice raises important environmental concerns related to the emergence of antimicrobial‐resistant bacteria strains. Only a few antimicrobial drugs have been approved for use in aquaculture, one of which is florfenicol. This work studies the depletion and withdrawal period of florfenicol and its main metabolite, florfenicol amine, in pacu (Piaractus mesopotamicus), a neotropical characin widely farmed in the southern hemisphere. Juvenile pacu (average weight of 724 g) were stocked in a closed‐loop laboratory system with controlled water temperature (25.8°C), and were fed for 10 consecutive days with a diet containing an intended dose of 10 mg/florfenicol per kg bw. Muscle and skin tissues were collected at 1, 3, 6, 8, 10, 12 and 16 days post‐treatment, and florfenicol and florfenicol amine were quantified using a validated ultra‐high performance liquid chromatography‐tandem mass spectrometry (UPLC‐MS/MS) method. The limits of quantitation for florfenicol and florfenicol amine were 10 ng/g in muscle and 50 ng/g in skin. Considering a maximum residue limit of 1000 ng/g for the sum of florfenicol and florfenicol amine in muscle with skin in natural proportions a withdrawal period of 5 days (water temperature 25.8°C) or 129 degree days was calculated on the basis of the upper limit of the one‐sided 95% confidence interval for the 99th percentile derived from the residue depletion study. 相似文献
63.
64.
Antonia Euflosina Dos Santos Iracema Andrade Nascimento 《Aquaculture (Amsterdam, Netherlands)》1985,47(4):335-352
Laboratory experiments were undertaken to determine the optimal environmental conditions and some of the other factors concerned in the development of Crassostrea rhizophorae embryos.Critical variables such as the number of spermatozoa per ovocyte during fertilization, the time of fertilization after gamete liberation, egg density, temperature and salinity were related to the proportion of normal D-larvae of C. rhizophorae in the resulting broods.The highest proportion of normal D-larvae was obtained at concentrations of 500–5000 spermatozoa/ovocyte, under conditions of 25‰ salinity at 25 ± 1°C. The optimal density of eggs, for the production of normal D-larvae, was 104?4 × 104 ovocytes/l. If fertilization was delayed for more than 45 min after liberation of spermatozoa the proportion of normal D-larvae was greatly reduced. The experiments demonstrated that the temperature for developing embryos should be below 30°C. At 20 and 25°C there was a high proportion of normal D-larvae 24 h after fertilization. The ideal salinity for embryonic development in C. rhizophorae was 25–37‰. Below a salinity of 16‰, less than 2.5% of the D-larvae were normal. 相似文献
65.
Roberto Venegas Thomas Oliver Russell E. Brainard Mudjekeewis Santos Rollan Geronimo Matthew Widlansky 《Fisheries Oceanography》2019,28(2):117-130
We investigated projected changes in sea surface temperature (SST) and the associated impacts on spawning habitat for skipjack tuna (Katsuwonus pelamis) in the Coral Triangle region (CT). A multimodel aggregate of SST CMIP5 models for the CT region, based on a comprehensive skill validation assessment, was used to identify the five best performing of 36 models tested for inclusion in a regional multimodel ensemble. Monthly 1° SST multimodel aggregate projections for the CT region under RCP8.5 show that increases in SST, as high as 2.8°C (mean value), will likely occur by the end of this century. Using these estimates of SST change, we applied three parameterizations of skipjack tuna spawning temperatures to assess the potential for change in spawning habitat within the CT region. The three spawning temperature parameterizations were as follows: (a) a square‐wave function derived from catch data with boundaries at 26 and 30°C; (b) a symmetric Gaussian function derived from the SEAPODYM models; and (c) an asymmetric Gaussian function that modifies the SEAPODYM curve in (b) to include the results of relevant physiological experiments. All three parameterizations show similar geographic patterns, with the amount of favourable spawning habitat decreasing throughout the central, equatorial CT region and increasing at higher latitudes. However, the three parameterizations show marked differences in the modelled magnitude of change, with an asymmetric Gaussian function (ASGF) showing a regionwide average of 66.1% decline in favourable spawning habitat between 2015 and 2099. These projected changes in tuna spawning habitats are likely to have important consequences on local and regional fisheries management in the CT region. 相似文献
66.
Thiago Luiz Da Mata Monique Inês SegerenAline Segeren Fonseca Carlos Augusto Colombo 《Scientia Horticulturae》2009
Genetic diversity was evaluated by RAPD markers and morpho-agronomic characters for a total of 42 accessions of Barberton daisy (Gerbera jamesonii) consisting of 29 commercial and 13 wild accessions. A total of 74 polymorphic bands were obtained employing a set of 12 primer pairs. The average genetic similarity coefficient for the 42 accessions, evaluated by Jaccard index was 0.55 ranging from 0.28 to 1.00. The genetic structure found among Barberton daisy accessions was evaluated by hierarchic classification analyses and UPGMA modeling, revealing six clusters of genotypes where two of them include the wild accessions and the remaining four including commercial material, except for wild genotype number 9. Shannon (H′) index was calculated using the molecular markers to investigate the genetic variation among the Gerbera accessions and showed higher values for the commercial cluster in comparison to the values obtained for the individuals from the non-commercial cluster, namely 0.34 versus 0.27, respectively. Therefore, both calculated indices (Jaccard and Shannon) indicated the presence of higher genetic variation among commercial accessions in comparison to the cluster representing non-commercial accessions, suggesting that genetic breeding programs may focus on commercial accessions to recombine interesting genotypes with commercially important and marketing-desired characteristics. 相似文献
67.
Igo G. Guimarães Luiz E. Pezzato Margarida M. Barros Leonardo Tachibana 《Journal of the World Aquaculture Society》2008,39(6):781-789
Apparent digestibility coefficients (ADCs) provide estimates of nutrient availability in feedstuffs and can be used as a tool for selecting ingredients to compound cost‐effective diets for fish. Extrusion process is one factor that could influence ADC values. Thus, a digestibility trial was undertaken to evaluate ADC of protein, energy, and dry matter, and apparent amino acid availability (AAAA) in five cereal grain products/by‐products (corn, wheat middlings, broken rice, rice bran, and sorghum) in compounded diets for Nile tilapia. Chromic oxide was used as an external inert marker. The digestibility values of energy and dry matter in ingredients, in decreasing order, were highest for broken rice (95.34 and 96.45%), sorghum (82.37 and 87.29%), corn (67.34 and 82.21%), rice bran (57.58 and 55.59%), and wheat middlings (48.94 and 45.88%). Protein digestibility value was higher for corn (72.86%) and the lowest value was observed for sorghum (56.77%), while broken rice, wheat middlings, and rice bran presented values ranging from 63.01 to 66.88%. AAAA values were higher for corn (70.05%) and the lowest methionine and cystine availability values were recorded for wheat middlings and broken rice, respectively. Broken rice appears as one of the most indicated ingredient for using in Nile tilapia diets because of its highest values of nutrient digestibility when compared to the other energetic sources. The use of this information should aid more precise and economic diet formulation for Nile tilapia. 相似文献
68.
The effects of different diets (natural or pellets) on growth, survival, and moulting interval of juvenile spider crabs, weighing
between 0.011–1.56 g and up to 17.6 mm in carapace length, were tested over a period of 90 days. During experiment I, five
diets were tested: (1) frozen shrimp—Paleomonetes sp., (2) fresh mussels—Mytilus sp., (3) white fish fillets—Merlucius merlucius, (4) blue fish fillets—Sardina pilchardus, and (5) commercial crustacean pellets. Spider crabs fed fresh mussels grew larger (0.98 ± 0.69 g) and had higher growth
rates (4.0 ± 0.7 %BWd−1) compared to the other four diets. The crabs fed shrimp pellet and frozen shrimp grew to intermediate sizes and were smaller
than the ones fed fresh mussels, but they were larger than spider crabs fed either blue or white fish fillets (0.46 ± 0.63
and 0.26 ± 0.13 g, respectively) compared to the ones fed white fish fillets (0.12 ± 0.04) and blue fish fillets (0.04 ± 0.02 g).
The spider crabs fed blue fish fillets only lasted until day 60 of the experiment, after this day none of the 20 fed this
diet were left. During experiment II, two diets were tested: (1) white and blue fish fillets and (2) commercial fish pellet.
There were no differences in growth both in weight or carapace length (2.9 ± 1.8 and 2.1 ± 1.5 g in weight, and 18.9 ± 5.0
and 17.7 ± 3.3 mm, respectively) at the end of the experiment. Similarly, there were no differences in growth rates in weight
between the two diets (1.2 ± 0.4 and 0.9 ± 0.3 %BWd−1, respectively) or in carapace length (0.4 ± 0.1 and 0.4 ± 0.2 %BWd−1, respectively). Fresh mussel appears to be a very good diet to culture the early stages of this species, while shrimp pellets
also deliver acceptable results. On the contrary, frozen shrimp, fish fillets either from blue or white species (much higher
lipid content in the blue species), and fish pellets were found to be bad diets for the culture of the early stages of M. brachydactyla. 相似文献
69.
Valentão P Andrade PB Rangel J Ribeiro B Silva BM Baptista P Seabra RM 《Journal of agricultural and food chemistry》2005,53(12):4925-4931
To check the influence of the conservation procedure in the chemical composition of chanterelle mushroom, phenolic compounds and organic acids of samples preserved under four different conditions (drying, freezing, conservation in olive oil and in vinegar) were determined. Phenolics and organic acids were analyzed by HPLC-DAD and HPLC-UV, respectively. The results showed that chanterelle is characterized by the presence of six phenolic compounds (3-, 4-, and 5-O-caffeoylquinic acid, caffeic acid, p-coumaric acid, and rutin) and five organic acids (citric, ascorbic, malic, shikimic, and fumaric acids). Samples preserved in olive oil also exhibited hydroxytyrosol, tyrosol, luteolin, and apigenin, whereas conservation in vinegar led to the detection of hydroxytyrosol, tyrosol, and tartaric acid in the analyzed samples. The conservation procedures to which chanterelle samples were subjected seem to affect the qualitative and quantitative phenolics and organic acids profiles. 相似文献
70.
Fernández M Picó Y Girotti S Mañes J 《Journal of agricultural and food chemistry》2001,49(8):3540-3547
Pesticides applied in extended agricultural fields may be controlled by means of bioindicators, such as honeybees, in which are the pesticides bioaccumulate. Liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS) experiments with positive (PI) and negative (NI) ion modes were optimized for the analysis of 22 organophosphorus pesticides in honeybee samples. The extraction required 3 g of sample, which was extracted with acetone. The extract was purified with coagulating solution and reextracted with Cl(2)CH(2). Pesticides studied could be detected by both ionization modes except for parathion, parathion-methyl, and bromophos, which did not give signals in PI mode, and triazophos, which was not detected in NI mode. Fragmentation voltage and vaporizer temperature were optimized to achieve the highest sensitivity. The spectra profile of each pesticide in PI mode showed the [M + H](+) ion as the main signal, whereas in NI mode only fragment ions were shown. The detection limit obtained in selected ion monitoring mode ranged from 1 to 15 microg kg(-1). The average recoveries from spiked honeybees at various concentration levels (0.5-5 mg kg(-1)) exceeded 65% with relative standard deviations of 4-15%. The method was applied to real samples, in which residues of coumaphos and dimethoate were detected. 相似文献